Boat survey technology

[jenevers]

Is there technology these days that allows hull thickness testing without having to spot grind into the metal?

[Alan de Enfield]

13 minutes ago, jenevers said:

Is there technology these days that allows hull thickness testing without having to spot grind into the metal?

 

 

Yes.

[Hudds Lad]

5 minutes ago, Alan de Enfield said:

 

 

Yes.

 

[jenevers]

8 minutes ago, Alan de Enfield said:

 

 

Yes.

Care to elaborate?

[Alan de Enfield]

Just now, jenevers said:

Care to elaborate?

 

Sorry, just answering the question.

 

Yes, new (very expensive) ultrasound thickness testers are available that can differentiate between 'paint' and steel. It measures the total thickness and then deducts the thickness of the paint giving you steel thickness without having to remove the paint.

 

Apparently some surveyors have purchased these testers but due to the cost many / most have not.

 

It is probably a 'spin-off' from testing pipelines or constuction steels or such like and, as the volumes grow, will no doubt come down in price.

[GRLMK38]

47 minutes ago, Alan de Enfield said:

 

Sorry, just answering the question.

 

Yes, new (very expensive) ultrasound thickness testers are available that can differentiate between 'paint' and steel. It measures the total thickness and then deducts the thickness of the paint giving you steel thickness without having to remove the paint.

 

Apparently some surveyors have purchased these testers but due to the cost many / most have not.

 

It is probably a 'spin-off' from testing pipelines or constuction steels or such like and, as the volumes grow, will no doubt come down in price.

 

The OP has not specified which areas are to be tested but it's true that they perform well on a relatively flat painted surface but even the good ones are fussy on corroded steel e.g. narrowboat bottom plates.  Spot grinding is sometimes the only option. 

[OldGoat]

All good stuff - but

The laf of sods suggests that if a hull thickness test is needed then it's probably time to have the boat re-blacked anyway!

Technically i may be possible to do a test while the boat is in the water - but I don't think a surveyor would want to do it that way.

[jenevers]

4 hours ago, OldGoat said:

All good stuff - but

The laf of sods suggests that if a hull thickness test is needed then it's probably time to have the boat re-blacked anyway!

Technically i may be possible to do a test while the boat is in the water - but I don't think a surveyor would want to do it that way.

Yes but I once saw a surveyor use a 5” grinder and take a good 1 mm (if not 2 mm) of steel off in spot grinding a hull. Disgraceful  in my opinion. Probably trying to get business for the boatyard.

[cheesegas]

23 hours ago, OldGoat said:

All good stuff - but

The laf of sods suggests that if a hull thickness test is needed then it's probably time to have the boat re-blacked anyway!

Technically i may be possible to do a test while the boat is in the water - but I don't think a surveyor would want to do it that way.

Last year I was going to purchase a beautifully painted, freshly blacked boat. Survey showed that the paint was covering up a lot of very thin spots...had to paint over the ground down parts before pulling out of the sale, pronto!

[blackrose]

On 30/03/2021 at 08:54, jenevers said:

Is there technology these days that allows hull thickness testing without having to spot grind into the metal?

 

Surely they grind into the paint, not the metal? A wire wheel on an angle grinder will remove paint but not metal.

[Detling]

Yes there is and if any surveyor was to use another typr on my boat he would be getting a bill, it was shot blasted, zingered and epoxied at great expense not for some cowboy to grind it off and if lucky, stick some bitumen on in the hope it will stay on when the boat is floated a few hours later. The intruments are not cheap but probably a lot cheaper than a lawyers bill.

[jenevers]

On 31/03/2021 at 21:30, blackrose said:

 

Surely they grind into the paint, not the metal? A wire wheel on an angle grinder will remove paint but not metal.

That's what I would insist on, having seen what happened with the guy with the grinder.